You can make an argument that Ritz' 2009 World Championship 10K run is still the greatest 10K performance ever by an American in recent years. He ran 27:22 in less than ideal conditions and without even pacing. He finished 6th.
I've watched that race several times now and its interesting to hear the British commentators as Ritz crosses the finish. There is a hint of a double take thinking he has another lap left.
And Ritz was borderline ecstatic about his performance after the race.